SpecBAS incorporates all the features of Sinclair BASIC, but with more:
Procedures, with both referenced and normal variable parameters
Flow control with DO..LOOP, WHILE..LOOP, DO..UNTIL
Better array handling, with variable BASE settings and FOR..EACH support
Better string handling with LEFT$, RIGHT$, MID$, REPEAT$ etc
Memory banks which can be loaded, saved and utilised to hold a variety of data types
Many, many more maths functions, with both radians and degrees support
Graphics with 8bpp in any supported resolution with full palette changing, rotation, scaling etc
Sound support with MOD/S3M/XM/IT/MP3/VOC/WAV etc
Turtle graphics, sprites, tilemaps.